In the product description is "easy to assemble" but easily is something else. You have to unscrew the complete rotor and from stuck, so far so good, and then solve even the rotor axis at the bottom of the large white gear. That's a little more difficult, because one has yet to unscrew the pedestal for it. But once changed this bar does exactly what they want, namely just rotate. Jerky now and vibrates the whole helicopter no longer after he crashed into a tree, because he came out of the reach of the remote control.
So if your rotor uncontrolled trundles and vibrates, this bar is really a good attempt to get the whole round again. The packaging was great, wrapped in bubble wrap, survived both the shipping and transport in the trunk. Is now re-flown
